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Author Topic: Light Table  (Read 927 times)

Kanvas Keepsakes

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Light Table
« on: August 21, 2014, 07:40:28 PM »

Hello everyone.  Wasn't sure where to post this discussion.  A buddy of mine is going to come by and build a light table for me.  I already have a large wooden work table with a big area on top that we can use to make a light table.  Anyone familiar with what kind of lights to put and what kind of material to cover them with?  Fiberglass?  I saw one online but haven't been able to find exactly what lighting to use.  Any help is much appreciated.  Thanks
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Garnick

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Re: Light Table
« Reply #1 on: August 21, 2014, 10:41:21 PM »

If you're using the light table for viewing photographic work, transparencies etc., I would suggest using 5000ēK fluorescent tubes.  The top could be opal plexiglass topped by a sheet of 1/4" plate glass to protect it from scratches, dirt etc.  I've built a number of these over the years and they work great.  I'm sure others here will suggest different methods and materials , but this is one possibility at least.  Hope this is of some help.

Gary   
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Ernst Dinkla

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Re: Light Table
« Reply #2 on: August 22, 2014, 06:50:13 AM »

Check some shops that sell secondhand graphic or photographic equipment. Too many printers went bankrupt, too many photographers switched from slides to digital in the last decades. I have a Just Normlight box from a similar source and very cheap, about 4x3 feet, that can be put on a table. Check the hours counter that usually is built in, it tells you whether the lamps need to be replaced.

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rgs

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Re: Light Table
« Reply #3 on: August 22, 2014, 07:23:12 AM »

Paint the inside matte white to avoid hot spots. Use translucent plexiglass on top. Putting a piece of glass over that to avoid scratches is a good idea. My current one uses 6 full spectrum CFLs that I found at a lighting supply store. You need full spectrum florescents of some type to get accurate color balance. 

Garnick

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Re: Light Table
« Reply #4 on: August 22, 2014, 09:51:14 AM »

Paint the inside matte white to avoid hot spots. Use translucent plexiglass on top. Putting a piece of glass over that to avoid scratches is a good idea. My current one uses 6 full spectrum CFLs that I found at a lighting supply store. You need full spectrum florescents of some type to get accurate color balance. 

Ah yes, I forgot about the FLAT white paint business, very important.  5000K tubes, full spectrum and a CRI(Colour Rendering Index) of at least 90, if you can find them.  Otherwise, as close to that number as possible.  Here the translucent plexiglass is called Opal, but it's basically the same product, although I've always been of the impression that Opal is slightly more white.  Of course you can also use Opal glass, but rather expensive and you still need the plate glass on top to protect your investment.  The 1/4" plate glass topping also tends to provide a more rigid surface to work on than the plexiglass alone.  When I was building these things I would always ask for 1/4" Salvage plate glass.  Perhaps a few slight scratches, but nothing to hinder your viewing and you can save a lot of money.

Gary
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DeanChriss

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Re: Light Table
« Reply #5 on: August 22, 2014, 02:42:02 PM »

5000K tubes, full spectrum and a CRI(Colour Rendering Index) of at least 90, if you can find them. 
Gary

I saw these just two days ago at a Home Depot. I use them in all of my fluorescent ceiling lamps for color accurate general illumination.
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Garnick

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Re: Light Table
« Reply #6 on: August 23, 2014, 12:15:19 PM »

I saw these just two days ago at a Home Depot. I use them in all of my fluorescent ceiling lamps for color accurate general illumination.

Hello Dean,

Was this in a Canadian Home Depot, and were they the T8 size(15/16" / 24mm diameter)?  I haven't seen them here in Canada, and the ones I had installed initially were Sylvania and supposedly a CRI of 90.  Recently when I checked the Sylvania site for that same bulb it was listed as CRI-80.  I was obviously mislead by our local Utilities company, who were installing these bulbs and ballasts at a minimal cost to businesses as an energy saving combination.  Hopefully Home Depot here in the great white north have now started carrying these tubes as well.  Thanks for the heads-up Dean.

Gary
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DeanChriss

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Re: Light Table
« Reply #7 on: August 24, 2014, 12:09:15 PM »

Gary,

Sorry for the late reply. I've been trying to enjoy what's left of summer.

Unfortunately what I saw was in the US and they were T12 tubes, but a little digging online finds:

http://www.amazon.com/Full-Spectrum-Fluorescent-Lamps-PHILIPS-950/dp/B0009INXIO (need to buy a whole case)

http://www.amazon.com/gp/product/B002DR5U9Y/ref=pd_lpo_sbs_dp_ss_1?pf_rd_p=1535523722&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B0009INXIO&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1GD89AAGKPV8N5XXRK9E

https://www.1000bulbs.com/pdf/Philips-TL90SeriesT8-Brochure.pdf

I hope this helps!

Dean


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